Consider yourself cultured if you own at least one of their nine albums.

These indie kings of New York City have married Jamaican roots with English ska and American ’60s garage rock since 1991. For 20 years they’ve booked their own gigs, moved their own gear, and invigorated crowds all over the world. And they’ve done it without the backing of a big label.

“We never made it in a pop way. And maybe we made some choices that kept us away from anything very commercial,” bandleader Vic Ruggiero acknowledged over the phone. “We’ve embraced a kind of an underground philosophy. It works for us.”

As the Slackers ready Stash Box, a rocksteady retrospective culled entirely from vinyl, the band will make its second appearance at Crowbar Tuesday. The group performs with the Duppies and Tribal Style at 8 p.m. Tuesday Tickets are $12-$15. Click here for details.

How do you keep a band together — and under the radar — for 20 years?

I like to say that we’re all stubborn and unimaginative. We just don’t know what to do next, so we just keep makin’ records.

The Slackers embody so many types of music, but don’t sound quite like anyone.

We knew that we wanted to play everything, and our problem was that we were kind of schizophrenic in our styles. … We were frustrated with ourselves ’cause we couldn’t figure out why we didn’t sound right. And then we realized, “Oh, you know what it is? We’re trying to play punk, and these aren’t punk musicians. We’re trying to play 2 Tone, and we’re not English New-Wave guys that are all stressed out.” So we found our sound. With boogie-woogie and a kind of a weird, retroey sound, we felt at home, you know?

You do have a knack for making depression sound so good.

People think it’s this happy goof music because it’s got this really up, fun beat, but (they’re) not realizing that it is coming from a deep and dark place in some ways. I mean, not in some ways, but...

There’s murder, adultery, Republicans ...

There’s a lot to write about, and there’s a lot that reggae and ska and punk kids — and everybody, for that matter — should be writing about, ’cause that’s your job as an artist, is to put the word out on the streets. The TV ain’t gonna do it, ’cause it ain’t in their interest to do it.

What else inspires you to write?

I keep my ears open to the world, you know? I listen to what people say when they walk by. Especially if they’re having an argument with each other. I’m not sayin’ that I’m eavesdroppin’ like a creep sitting behind people making out on a bench or somethin’. But I listen. People give me words. … In a way, it’s not even us that’s writing. We’re like antennas that just pick stuff up. You’re a radio, and you tune your dial around, you find a voice, and then you go with it. Between the static you try and pick out the melody.

I always wondered why the Slackers never broke through to radio.

We wonder, too. ’Cause it’s not that we weren’t trying to make music that’s up to that level, ’cause we are. And we think that our music is better than the music that’s on the radio. Obviously. It’s a cliche — nobody likes the music on the radio.

You taught yourself to play piano as a child, but it seems you play everything today.

Yeah, I have a storage base full of instruments. It’s a moldy basement full of moldy instruments that make me sneeze when I play them. … One of the reasons that I like to play different instruments is ’cause it’ll bring something different out of me if I’m in a rut.

Why compile a greatest-hits album?

It seemed like the right thing to do. We’re always getting new fans, and they want to know what record to buy. So we polled our audience (via Facebook) and asked them what they would show off to someone to get them into the Slackers, and we got 19 songs. I took it all off vinyl. I found every bit of vinyl that we had, and that was my concept for it. … We figured with this concept that people are getting to know us. We want them to know what we like, and what we like is vinyl.

Tell me we’ll be hearing from the Slackers 20 years from now.

We hope that it changes the world and creates world peace and harmony, and aligns the planets and whatever. But until that day, we’re just gonna be happy that a couple of people ask us to play at their wedding, because they said, “This is the song we fell in love to.” Or, “You made me feel okay to tell the other people in my class that I did not agree with right-wing politics.” (Laughs)